16., if 3 men with 4 boys can ear a Rs.2100 in 7 days, and 11 men with

1.	16., if 3 men with 4 boys can ear a Rs.2100 in 7 days, and 11 men with 13 boys can earn Rs.8300 in 8 days, in what timewill 7 men with 9 boys earn Rs.11000?(a) 16 days(b 17 days(c) 18 days(d) 20 days
Answer» Let m and n be the money earned by a boy and a man in 1 day. Then, we have 3m + 4n = 2100/7 ⇒3m + 4n = 300 ----------[1] And 11m + 13n = 8300/8 ⇒11m + 13n = 1037.5 –------[2] Solving [1] and [2], we get We get m = 50 and n = 37.5 Now we need to find k where ⇒ k(7m + 9n) = 11000 ⇒ k(7 × 50 + 9 × 37.5) = 11000 ⇒ 687.5 × k = 11000 ⇒ k = 11000/687.5 ⇒ k = 16

16., if 3 men with 4 boys can ear a Rs.2100 in 7 days, and 11 men with 13 boys can earn Rs.8300 in 8 days, in what timewill 7 men with 9 boys earn Rs.11000?(a) 16 days(b 17 days(c) 18 days(d) 20 days

Answer»

Let m and n be the money earned by a boy and a man in 1 day.

Then, we have

3m + 4n = 2100/7

⇒3m + 4n = 300 ----------[1]

And

11m + 13n = 8300/8

⇒11m + 13n = 1037.5 –------[2]

Solving [1] and [2], we get

We get m = 50 and n = 37.5

Now we need to find k where

⇒ k(7m + 9n) = 11000

⇒ k(7 × 50 + 9 × 37.5) = 11000

⇒ 687.5 × k = 11000

⇒ k = 11000/687.5

⇒ k = 16